1 /* Control and data flow functions for trees.
2    Copyright 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
3    Contributed by Alexandre Oliva <aoliva@redhat.com>
4 
5 This file is part of GCC.
6 
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
10 any later version.
11 
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 GNU General Public License for more details.
16 
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING.  If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA.  */
21 
22 #include "config.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "toplev.h"
27 #include "tree.h"
28 #include "tree-inline.h"
29 #include "rtl.h"
30 #include "expr.h"
31 #include "flags.h"
32 #include "params.h"
33 #include "input.h"
34 #include "insn-config.h"
35 #include "integrate.h"
36 #include "varray.h"
37 #include "hashtab.h"
38 #include "splay-tree.h"
39 #include "langhooks.h"
40 #include "cgraph.h"
41 #include "intl.h"
42 #include "diagnostic.h"
43 
44 /* This should be eventually be generalized to other languages, but
45    this would require a shared function-as-trees infrastructure.  */
46 #ifndef INLINER_FOR_JAVA
47 #include "c-common.h"
48 #else /* INLINER_FOR_JAVA */
49 #include "parse.h"
50 #include "java-tree.h"
51 #endif /* INLINER_FOR_JAVA */
52 
53 /* 0 if we should not perform inlining.
54    1 if we should expand functions calls inline at the tree level.
55    2 if we should consider *all* functions to be inline
56    candidates.  */
57 
58 int flag_inline_trees = 0;
59 
60 /* To Do:
61 
62    o In order to make inlining-on-trees work, we pessimized
63      function-local static constants.  In particular, they are now
64      always output, even when not addressed.  Fix this by treating
65      function-local static constants just like global static
66      constants; the back-end already knows not to output them if they
67      are not needed.
68 
69    o Provide heuristics to clamp inlining of recursive template
70      calls?  */
71 
72 /* Data required for function inlining.  */
73 
74 typedef struct inline_data
75 {
76   /* A stack of the functions we are inlining.  For example, if we are
77      compiling `f', which calls `g', which calls `h', and we are
78      inlining the body of `h', the stack will contain, `h', followed
79      by `g', followed by `f'.  The first few elements of the stack may
80      contain other functions that we know we should not recurse into,
81      even though they are not directly being inlined.  */
82   varray_type fns;
83   /* The index of the first element of FNS that really represents an
84      inlined function.  */
85   unsigned first_inlined_fn;
86   /* The label to jump to when a return statement is encountered.  If
87      this value is NULL, then return statements will simply be
88      remapped as return statements, rather than as jumps.  */
89   tree ret_label;
90   /* The map from local declarations in the inlined function to
91      equivalents in the function into which it is being inlined.  */
92   splay_tree decl_map;
93   /* Nonzero if we are currently within the cleanup for a
94      TARGET_EXPR.  */
95   int in_target_cleanup_p;
96   /* A list of the functions current function has inlined.  */
97   varray_type inlined_fns;
98   /* We use the same mechanism to build clones that we do to perform
99      inlining.  However, there are a few places where we need to
100      distinguish between those two situations.  This flag is true if
101      we are cloning, rather than inlining.  */
102   bool cloning_p;
103   /* Hash table used to prevent walk_tree from visiting the same node
104      umpteen million times.  */
105   htab_t tree_pruner;
106   /* Decl of function we are inlining into.  */
107   tree decl;
108   tree current_decl;
109 } inline_data;
110 
111 /* Prototypes.  */
112 
113 static tree declare_return_variable (inline_data *, tree, tree *);
114 static tree copy_body_r (tree *, int *, void *);
115 static tree copy_body (inline_data *);
116 static tree expand_call_inline (tree *, int *, void *);
117 static void expand_calls_inline (tree *, inline_data *);
118 static bool inlinable_function_p (tree);
119 static tree remap_decl (tree, inline_data *);
120 static tree remap_type (tree, inline_data *);
121 #ifndef INLINER_FOR_JAVA
122 static tree initialize_inlined_parameters (inline_data *, tree, tree);
123 static void remap_block (tree, tree, inline_data *);
124 static void copy_scope_stmt (tree *, int *, inline_data *);
125 #else /* INLINER_FOR_JAVA */
126 static tree initialize_inlined_parameters (inline_data *, tree, tree, tree);
127 static void remap_block (tree *, tree, inline_data *);
128 static tree add_stmt_to_compound (tree, tree, tree);
129 #endif /* INLINER_FOR_JAVA */
130 
131 /* Remap DECL during the copying of the BLOCK tree for the function.  */
132 
133 static tree
remap_decl(tree decl,inline_data * id)134 remap_decl (tree decl, inline_data *id)
135 {
136   splay_tree_node n;
137   tree fn;
138 
139   /* We only remap local variables in the current function.  */
140   fn = VARRAY_TOP_TREE (id->fns);
141   if (! (*lang_hooks.tree_inlining.auto_var_in_fn_p) (decl, fn))
142     return NULL_TREE;
143 
144   /* See if we have remapped this declaration.  */
145   n = splay_tree_lookup (id->decl_map, (splay_tree_key) decl);
146 
147   /* If we didn't already have an equivalent for this declaration,
148      create one now.  */
149   if (!n)
150     {
151       tree t;
152 
153       /* Make a copy of the variable or label.  */
154       t = copy_decl_for_inlining (decl, fn, VARRAY_TREE (id->fns, 0));
155 
156       /* Remap types, if necessary.  */
157       TREE_TYPE (t) = remap_type (TREE_TYPE (t), id);
158       if (TREE_CODE (t) == TYPE_DECL)
159         DECL_ORIGINAL_TYPE (t) = remap_type (DECL_ORIGINAL_TYPE (t), id);
160       else if (TREE_CODE (t) == PARM_DECL)
161         DECL_ARG_TYPE_AS_WRITTEN (t)
162 	  = remap_type (DECL_ARG_TYPE_AS_WRITTEN (t), id);
163 
164       /* Remap sizes as necessary.  */
165       walk_tree (&DECL_SIZE (t), copy_body_r, id, NULL);
166       walk_tree (&DECL_SIZE_UNIT (t), copy_body_r, id, NULL);
167 
168 #ifndef INLINER_FOR_JAVA
169       if (! DECL_NAME (t) && TREE_TYPE (t)
170 	  && (*lang_hooks.tree_inlining.anon_aggr_type_p) (TREE_TYPE (t)))
171 	{
172 	  /* For a VAR_DECL of anonymous type, we must also copy the
173 	     member VAR_DECLS here and rechain the DECL_ANON_UNION_ELEMS.  */
174 	  tree members = NULL;
175 	  tree src;
176 
177 	  for (src = DECL_ANON_UNION_ELEMS (t); src;
178 	       src = TREE_CHAIN (src))
179 	    {
180 	      tree member = remap_decl (TREE_VALUE (src), id);
181 
182 	      if (TREE_PURPOSE (src))
183 		abort ();
184 	      members = tree_cons (NULL, member, members);
185 	    }
186 	  DECL_ANON_UNION_ELEMS (t) = nreverse (members);
187 	}
188 #endif /* not INLINER_FOR_JAVA */
189 
190       /* Remember it, so that if we encounter this local entity
191 	 again we can reuse this copy.  */
192       n = splay_tree_insert (id->decl_map,
193 			     (splay_tree_key) decl,
194 			     (splay_tree_value) t);
195     }
196 
197   return (tree) n->value;
198 }
199 
200 static tree
remap_type(tree type,inline_data * id)201 remap_type (tree type, inline_data *id)
202 {
203   splay_tree_node node;
204   tree new, t;
205 
206   if (type == NULL)
207     return type;
208 
209   /* See if we have remapped this type.  */
210   node = splay_tree_lookup (id->decl_map, (splay_tree_key) type);
211   if (node)
212     return (tree) node->value;
213 
214   /* The type only needs remapping if it's variably modified.  */
215   if (! variably_modified_type_p (type))
216     {
217       splay_tree_insert (id->decl_map, (splay_tree_key) type,
218 			 (splay_tree_value) type);
219       return type;
220     }
221 
222   /* We do need a copy.  build and register it now.  */
223   new = copy_node (type);
224   splay_tree_insert (id->decl_map, (splay_tree_key) type,
225 		     (splay_tree_value) new);
226 
227   /* This is a new type, not a copy of an old type.  Need to reassociate
228      variants.  We can handle everything except the main variant lazily.  */
229   t = TYPE_MAIN_VARIANT (type);
230   if (type != t)
231     {
232       t = remap_type (t, id);
233       TYPE_MAIN_VARIANT (new) = t;
234       TYPE_NEXT_VARIANT (new) = TYPE_MAIN_VARIANT (t);
235       TYPE_NEXT_VARIANT (t) = new;
236     }
237   else
238     {
239       TYPE_MAIN_VARIANT (new) = new;
240       TYPE_NEXT_VARIANT (new) = NULL;
241     }
242 
243   /* Lazily create pointer and reference types.  */
244   TYPE_POINTER_TO (new) = NULL;
245   TYPE_REFERENCE_TO (new) = NULL;
246 
247   switch (TREE_CODE (new))
248     {
249     case INTEGER_TYPE:
250     case REAL_TYPE:
251     case ENUMERAL_TYPE:
252     case BOOLEAN_TYPE:
253     case CHAR_TYPE:
254       t = TYPE_MIN_VALUE (new);
255       if (t && TREE_CODE (t) != INTEGER_CST)
256         walk_tree (&TYPE_MIN_VALUE (new), copy_body_r, id, NULL);
257       t = TYPE_MAX_VALUE (new);
258       if (t && TREE_CODE (t) != INTEGER_CST)
259         walk_tree (&TYPE_MAX_VALUE (new), copy_body_r, id, NULL);
260       return new;
261 
262     case POINTER_TYPE:
263       TREE_TYPE (new) = t = remap_type (TREE_TYPE (new), id);
264       if (TYPE_MODE (new) == ptr_mode)
265         TYPE_POINTER_TO (t) = new;
266       return new;
267 
268     case REFERENCE_TYPE:
269       TREE_TYPE (new) = t = remap_type (TREE_TYPE (new), id);
270       if (TYPE_MODE (new) == ptr_mode)
271         TYPE_REFERENCE_TO (t) = new;
272       return new;
273 
274     case METHOD_TYPE:
275     case FUNCTION_TYPE:
276       TREE_TYPE (new) = remap_type (TREE_TYPE (new), id);
277       walk_tree (&TYPE_ARG_TYPES (new), copy_body_r, id, NULL);
278       return new;
279 
280     case ARRAY_TYPE:
281       TREE_TYPE (new) = remap_type (TREE_TYPE (new), id);
282       TYPE_DOMAIN (new) = remap_type (TYPE_DOMAIN (new), id);
283       break;
284 
285     case RECORD_TYPE:
286     case UNION_TYPE:
287     case QUAL_UNION_TYPE:
288       walk_tree (&TYPE_FIELDS (new), copy_body_r, id, NULL);
289       break;
290 
291     case FILE_TYPE:
292     case SET_TYPE:
293     case OFFSET_TYPE:
294     default:
295       /* Shouldn't have been thought variable sized.  */
296       abort ();
297     }
298 
299   walk_tree (&TYPE_SIZE (new), copy_body_r, id, NULL);
300   walk_tree (&TYPE_SIZE_UNIT (new), copy_body_r, id, NULL);
301 
302   return new;
303 }
304 
305 #ifndef INLINER_FOR_JAVA
306 /* Copy the SCOPE_STMT_BLOCK associated with SCOPE_STMT to contain
307    remapped versions of the variables therein.  And hook the new block
308    into the block-tree.  If non-NULL, the DECLS are declarations to
309    add to use instead of the BLOCK_VARS in the old block.  */
310 #else /* INLINER_FOR_JAVA */
311 /* Copy the BLOCK to contain remapped versions of the variables
312    therein.  And hook the new block into the block-tree.  */
313 #endif /* INLINER_FOR_JAVA */
314 
315 static void
316 #ifndef INLINER_FOR_JAVA
remap_block(tree scope_stmt,tree decls,inline_data * id)317 remap_block (tree scope_stmt, tree decls, inline_data *id)
318 #else /* INLINER_FOR_JAVA */
319 remap_block (tree *block, tree decls, inline_data *id)
320 #endif /* INLINER_FOR_JAVA */
321 {
322 #ifndef INLINER_FOR_JAVA
323   /* We cannot do this in the cleanup for a TARGET_EXPR since we do
324      not know whether or not expand_expr will actually write out the
325      code we put there.  If it does not, then we'll have more BLOCKs
326      than block-notes, and things will go awry.  At some point, we
327      should make the back-end handle BLOCK notes in a tidier way,
328      without requiring a strict correspondence to the block-tree; then
329      this check can go.  */
330   if (id->in_target_cleanup_p)
331     {
332       SCOPE_STMT_BLOCK (scope_stmt) = NULL_TREE;
333       return;
334     }
335 
336   /* If this is the beginning of a scope, remap the associated BLOCK.  */
337   if (SCOPE_BEGIN_P (scope_stmt) && SCOPE_STMT_BLOCK (scope_stmt))
338     {
339       tree old_block;
340       tree new_block;
341       tree old_var;
342       tree fn;
343 
344       /* Make the new block.  */
345       old_block = SCOPE_STMT_BLOCK (scope_stmt);
346       new_block = make_node (BLOCK);
347       TREE_USED (new_block) = TREE_USED (old_block);
348       BLOCK_ABSTRACT_ORIGIN (new_block) = old_block;
349       SCOPE_STMT_BLOCK (scope_stmt) = new_block;
350 
351       /* Remap its variables.  */
352       for (old_var = decls ? decls : BLOCK_VARS (old_block);
353 	   old_var;
354 	   old_var = TREE_CHAIN (old_var))
355 	{
356 	  tree new_var;
357 
358 	  /* Remap the variable.  */
359 	  new_var = remap_decl (old_var, id);
360 	  /* If we didn't remap this variable, so we can't mess with
361 	     its TREE_CHAIN.  If we remapped this variable to
362 	     something other than a declaration (say, if we mapped it
363 	     to a constant), then we must similarly omit any mention
364 	     of it here.  */
365 	  if (!new_var || !DECL_P (new_var))
366 	    ;
367 	  else
368 	    {
369 	      TREE_CHAIN (new_var) = BLOCK_VARS (new_block);
370 	      BLOCK_VARS (new_block) = new_var;
371 	    }
372 	}
373       /* We put the BLOCK_VARS in reverse order; fix that now.  */
374       BLOCK_VARS (new_block) = nreverse (BLOCK_VARS (new_block));
375       fn = VARRAY_TREE (id->fns, 0);
376       if (id->cloning_p)
377 	/* We're building a clone; DECL_INITIAL is still
378 	   error_mark_node, and current_binding_level is the parm
379 	   binding level.  */
380 	(*lang_hooks.decls.insert_block) (new_block);
381       else
382 	{
383 	  /* Attach this new block after the DECL_INITIAL block for the
384 	     function into which this block is being inlined.  In
385 	     rest_of_compilation we will straighten out the BLOCK tree.  */
386 	  tree *first_block;
387 	  if (DECL_INITIAL (fn))
388 	    first_block = &BLOCK_CHAIN (DECL_INITIAL (fn));
389 	  else
390 	    first_block = &DECL_INITIAL (fn);
391 	  BLOCK_CHAIN (new_block) = *first_block;
392 	  *first_block = new_block;
393 	}
394       /* Remember the remapped block.  */
395       splay_tree_insert (id->decl_map,
396 			 (splay_tree_key) old_block,
397 			 (splay_tree_value) new_block);
398     }
399   /* If this is the end of a scope, set the SCOPE_STMT_BLOCK to be the
400      remapped block.  */
401   else if (SCOPE_END_P (scope_stmt) && SCOPE_STMT_BLOCK (scope_stmt))
402     {
403       splay_tree_node n;
404 
405       /* Find this block in the table of remapped things.  */
406       n = splay_tree_lookup (id->decl_map,
407 			     (splay_tree_key) SCOPE_STMT_BLOCK (scope_stmt));
408       if (! n)
409 	abort ();
410       SCOPE_STMT_BLOCK (scope_stmt) = (tree) n->value;
411     }
412 #else /* INLINER_FOR_JAVA */
413   tree old_block;
414   tree new_block;
415   tree old_var;
416   tree fn;
417 
418   /* Make the new block.  */
419   old_block = *block;
420   new_block = make_node (BLOCK);
421   TREE_USED (new_block) = TREE_USED (old_block);
422   BLOCK_ABSTRACT_ORIGIN (new_block) = old_block;
423   BLOCK_SUBBLOCKS (new_block) = BLOCK_SUBBLOCKS (old_block);
424   TREE_SIDE_EFFECTS (new_block) = TREE_SIDE_EFFECTS (old_block);
425   TREE_TYPE (new_block) = TREE_TYPE (old_block);
426   *block = new_block;
427 
428   /* Remap its variables.  */
429   for (old_var = decls ? decls : BLOCK_VARS (old_block);
430        old_var;
431        old_var = TREE_CHAIN (old_var))
432     {
433       tree new_var;
434 
435       /* All local class initialization flags go in the outermost
436 	 scope.  */
437       if (LOCAL_CLASS_INITIALIZATION_FLAG_P (old_var))
438 	{
439 	  /* We may already have one.  */
440 	  if (! splay_tree_lookup (id->decl_map, (splay_tree_key) old_var))
441 	    {
442 	      tree outermost_block;
443 	      new_var = remap_decl (old_var, id);
444 	      DECL_ABSTRACT_ORIGIN (new_var) = NULL;
445 	      outermost_block = DECL_SAVED_TREE (current_function_decl);
446 	      TREE_CHAIN (new_var) = BLOCK_VARS (outermost_block);
447 	      BLOCK_VARS (outermost_block) = new_var;
448 	    }
449 	  continue;
450 	}
451 
452       /* Remap the variable.  */
453       new_var = remap_decl (old_var, id);
454       /* If we didn't remap this variable, so we can't mess with
455 	 its TREE_CHAIN.  If we remapped this variable to
456 	 something other than a declaration (say, if we mapped it
457 	 to a constant), then we must similarly omit any mention
458 	 of it here.  */
459       if (!new_var || !DECL_P (new_var))
460 	;
461       else
462 	{
463 	  TREE_CHAIN (new_var) = BLOCK_VARS (new_block);
464 	  BLOCK_VARS (new_block) = new_var;
465 	}
466     }
467   /* We put the BLOCK_VARS in reverse order; fix that now.  */
468   BLOCK_VARS (new_block) = nreverse (BLOCK_VARS (new_block));
469   fn = VARRAY_TREE (id->fns, 0);
470   /* Remember the remapped block.  */
471   splay_tree_insert (id->decl_map,
472 		     (splay_tree_key) old_block,
473 		     (splay_tree_value) new_block);
474 #endif /* INLINER_FOR_JAVA */
475 }
476 
477 #ifndef INLINER_FOR_JAVA
478 /* Copy the SCOPE_STMT pointed to by TP.  */
479 
480 static void
copy_scope_stmt(tree * tp,int * walk_subtrees,inline_data * id)481 copy_scope_stmt (tree *tp, int *walk_subtrees, inline_data *id)
482 {
483   tree block;
484 
485   /* Remember whether or not this statement was nullified.  When
486      making a copy, copy_tree_r always sets SCOPE_NULLIFIED_P (and
487      doesn't copy the SCOPE_STMT_BLOCK) to free callers from having to
488      deal with copying BLOCKs if they do not wish to do so.  */
489   block = SCOPE_STMT_BLOCK (*tp);
490   /* Copy (and replace) the statement.  */
491   copy_tree_r (tp, walk_subtrees, NULL);
492   /* Restore the SCOPE_STMT_BLOCK.  */
493   SCOPE_STMT_BLOCK (*tp) = block;
494 
495   /* Remap the associated block.  */
496   remap_block (*tp, NULL_TREE, id);
497 }
498 #endif /* not INLINER_FOR_JAVA */
499 
500 /* Called from copy_body via walk_tree.  DATA is really an
501    `inline_data *'.  */
502 static tree
copy_body_r(tree * tp,int * walk_subtrees,void * data)503 copy_body_r (tree *tp, int *walk_subtrees, void *data)
504 {
505   inline_data* id;
506   tree fn;
507 
508   /* Set up.  */
509   id = (inline_data *) data;
510   fn = VARRAY_TOP_TREE (id->fns);
511 
512 #if 0
513   /* All automatic variables should have a DECL_CONTEXT indicating
514      what function they come from.  */
515   if ((TREE_CODE (*tp) == VAR_DECL || TREE_CODE (*tp) == LABEL_DECL)
516       && DECL_NAMESPACE_SCOPE_P (*tp))
517     if (! DECL_EXTERNAL (*tp) && ! TREE_STATIC (*tp))
518       abort ();
519 #endif
520 
521 #ifdef INLINER_FOR_JAVA
522   if (TREE_CODE (*tp) == BLOCK)
523     remap_block (tp, NULL_TREE, id);
524 #endif
525 
526   /* If this is a RETURN_STMT, change it into an EXPR_STMT and a
527      GOTO_STMT with the RET_LABEL as its target.  */
528 #ifndef INLINER_FOR_JAVA
529   if (TREE_CODE (*tp) == RETURN_STMT && id->ret_label)
530 #else /* INLINER_FOR_JAVA */
531   if (TREE_CODE (*tp) == RETURN_EXPR && id->ret_label)
532 #endif /* INLINER_FOR_JAVA */
533     {
534       tree return_stmt = *tp;
535       tree goto_stmt;
536 
537       /* Build the GOTO_STMT.  */
538 #ifndef INLINER_FOR_JAVA
539       goto_stmt = build_stmt (GOTO_STMT, id->ret_label);
540       TREE_CHAIN (goto_stmt) = TREE_CHAIN (return_stmt);
541       GOTO_FAKE_P (goto_stmt) = 1;
542 #else /* INLINER_FOR_JAVA */
543       tree assignment = TREE_OPERAND (return_stmt, 0);
544       goto_stmt = build1 (GOTO_EXPR, void_type_node, id->ret_label);
545       TREE_SIDE_EFFECTS (goto_stmt) = 1;
546 #endif /* INLINER_FOR_JAVA */
547 
548       /* If we're returning something, just turn that into an
549 	 assignment into the equivalent of the original
550 	 RESULT_DECL.  */
551 #ifndef INLINER_FOR_JAVA
552       if (RETURN_STMT_EXPR (return_stmt))
553 	{
554 	  *tp = build_stmt (EXPR_STMT,
555 			    RETURN_STMT_EXPR (return_stmt));
556 	  STMT_IS_FULL_EXPR_P (*tp) = 1;
557 	  /* And then jump to the end of the function.  */
558 	  TREE_CHAIN (*tp) = goto_stmt;
559 	}
560 #else /* INLINER_FOR_JAVA */
561       if (assignment)
562 	{
563 	  copy_body_r (&assignment, walk_subtrees, data);
564 	  *tp = build (COMPOUND_EXPR, void_type_node, assignment, goto_stmt);
565 	  TREE_SIDE_EFFECTS (*tp) = 1;
566 	}
567 #endif /* INLINER_FOR_JAVA */
568       /* If we're not returning anything just do the jump.  */
569       else
570 	*tp = goto_stmt;
571     }
572   /* Local variables and labels need to be replaced by equivalent
573      variables.  We don't want to copy static variables; there's only
574      one of those, no matter how many times we inline the containing
575      function.
576      We do not also want to copy the label which we put into
577      GOTO_STMT which replaced RETURN_STMT.  */
578   else if (*tp != id->ret_label
579 	   && (*lang_hooks.tree_inlining.auto_var_in_fn_p) (*tp, fn))
580     {
581       tree new_decl;
582 
583       /* Remap the declaration.  */
584       new_decl = remap_decl (*tp, id);
585       if (! new_decl)
586 	abort ();
587       /* Replace this variable with the copy.  */
588       STRIP_TYPE_NOPS (new_decl);
589       *tp = new_decl;
590     }
591 #if 0
592   else if (nonstatic_local_decl_p (*tp)
593 	   && DECL_CONTEXT (*tp) != VARRAY_TREE (id->fns, 0))
594     abort ();
595 #endif
596   else if (TREE_CODE (*tp) == SAVE_EXPR)
597     remap_save_expr (tp, id->decl_map, VARRAY_TREE (id->fns, 0),
598 		     walk_subtrees);
599   else if (TREE_CODE (*tp) == UNSAVE_EXPR)
600     /* UNSAVE_EXPRs should not be generated until expansion time.  */
601     abort ();
602 #ifndef INLINER_FOR_JAVA
603   /* For a SCOPE_STMT, we must copy the associated block so that we
604      can write out debugging information for the inlined variables.  */
605   else if (TREE_CODE (*tp) == SCOPE_STMT && !id->in_target_cleanup_p)
606     copy_scope_stmt (tp, walk_subtrees, id);
607 #else /* INLINER_FOR_JAVA */
608   else if (TREE_CODE (*tp) == LABELED_BLOCK_EXPR)
609     {
610       /* We need a new copy of this labeled block; the EXIT_BLOCK_EXPR
611          will refer to it, so save a copy ready for remapping.  We
612          save it in the decl_map, although it isn't a decl.  */
613       tree new_block = copy_node (*tp);
614       splay_tree_insert (id->decl_map,
615 			 (splay_tree_key) *tp,
616 			 (splay_tree_value) new_block);
617       *tp = new_block;
618     }
619   else if (TREE_CODE (*tp) == EXIT_BLOCK_EXPR)
620     {
621       splay_tree_node n
622 	= splay_tree_lookup (id->decl_map,
623 			     (splay_tree_key) TREE_OPERAND (*tp, 0));
624       /* We _must_ have seen the enclosing LABELED_BLOCK_EXPR.  */
625       if (! n)
626 	abort ();
627       *tp = copy_node (*tp);
628       TREE_OPERAND (*tp, 0) = (tree) n->value;
629     }
630 #endif /* INLINER_FOR_JAVA */
631   /* Types may need remapping as well.  */
632   else if (TYPE_P (*tp))
633     *tp = remap_type (*tp, id);
634 
635   /* Otherwise, just copy the node.  Note that copy_tree_r already
636      knows not to copy VAR_DECLs, etc., so this is safe.  */
637   else
638     {
639       if (TREE_CODE (*tp) == MODIFY_EXPR
640 	  && TREE_OPERAND (*tp, 0) == TREE_OPERAND (*tp, 1)
641 	  && ((*lang_hooks.tree_inlining.auto_var_in_fn_p)
642 	      (TREE_OPERAND (*tp, 0), fn)))
643 	{
644 	  /* Some assignments VAR = VAR; don't generate any rtl code
645 	     and thus don't count as variable modification.  Avoid
646 	     keeping bogosities like 0 = 0.  */
647 	  tree decl = TREE_OPERAND (*tp, 0), value;
648 	  splay_tree_node n;
649 
650 	  n = splay_tree_lookup (id->decl_map, (splay_tree_key) decl);
651 	  if (n)
652 	    {
653 	      value = (tree) n->value;
654 	      STRIP_TYPE_NOPS (value);
655 	      if (TREE_CONSTANT (value) || TREE_READONLY_DECL_P (value))
656 		{
657 		  *tp = value;
658 		  return copy_body_r (tp, walk_subtrees, data);
659 		}
660 	    }
661 	}
662       else if (TREE_CODE (*tp) == ADDR_EXPR
663 	       && ((*lang_hooks.tree_inlining.auto_var_in_fn_p)
664 		   (TREE_OPERAND (*tp, 0), fn)))
665 	{
666 	  /* Get rid of &* from inline substitutions.  It can occur when
667 	     someone takes the address of a parm or return slot passed by
668 	     invisible reference.  */
669 	  tree decl = TREE_OPERAND (*tp, 0), value;
670 	  splay_tree_node n;
671 
672 	  n = splay_tree_lookup (id->decl_map, (splay_tree_key) decl);
673 	  if (n)
674 	    {
675 	      value = (tree) n->value;
676 	      if (TREE_CODE (value) == INDIRECT_REF)
677 		{
678 		  *tp = convert (TREE_TYPE (*tp), TREE_OPERAND (value, 0));
679 		  return copy_body_r (tp, walk_subtrees, data);
680 		}
681 	    }
682 	}
683 
684       copy_tree_r (tp, walk_subtrees, NULL);
685 
686       TREE_TYPE (*tp) = remap_type (TREE_TYPE (*tp), id);
687 
688       /* The copied TARGET_EXPR has never been expanded, even if the
689 	 original node was expanded already.  */
690       if (TREE_CODE (*tp) == TARGET_EXPR && TREE_OPERAND (*tp, 3))
691 	{
692 	  TREE_OPERAND (*tp, 1) = TREE_OPERAND (*tp, 3);
693 	  TREE_OPERAND (*tp, 3) = NULL_TREE;
694 	}
695     }
696 
697   /* Keep iterating.  */
698   return NULL_TREE;
699 }
700 
701 /* Make a copy of the body of FN so that it can be inserted inline in
702    another function.  */
703 
704 static tree
copy_body(inline_data * id)705 copy_body (inline_data *id)
706 {
707   tree body;
708 
709   body = DECL_SAVED_TREE (VARRAY_TOP_TREE (id->fns));
710   walk_tree (&body, copy_body_r, id, NULL);
711 
712   return body;
713 }
714 
715 /* Generate code to initialize the parameters of the function at the
716    top of the stack in ID from the ARGS (presented as a TREE_LIST).  */
717 
718 static tree
719 #ifndef INLINER_FOR_JAVA
initialize_inlined_parameters(inline_data * id,tree args,tree fn)720 initialize_inlined_parameters (inline_data *id, tree args, tree fn)
721 #else /* INLINER_FOR_JAVA */
722 initialize_inlined_parameters (inline_data *id, tree args, tree fn, tree block)
723 #endif /* INLINER_FOR_JAVA */
724 {
725   tree init_stmts;
726   tree parms;
727   tree a;
728   tree p;
729 #ifdef INLINER_FOR_JAVA
730   tree vars = NULL_TREE;
731 #endif /* INLINER_FOR_JAVA */
732   int argnum = 0;
733 
734   /* Figure out what the parameters are.  */
735   parms =
736 DECL_ARGUMENTS (fn);
737 
738   /* Start with no initializations whatsoever.  */
739   init_stmts = NULL_TREE;
740 
741   /* Loop through the parameter declarations, replacing each with an
742      equivalent VAR_DECL, appropriately initialized.  */
743   for (p = parms, a = args; p;
744        a = a ? TREE_CHAIN (a) : a, p = TREE_CHAIN (p))
745     {
746 #ifndef INLINER_FOR_JAVA
747       tree init_stmt;
748       tree cleanup;
749 #endif /* not INLINER_FOR_JAVA */
750       tree var;
751       tree value;
752       tree var_sub;
753 
754       ++argnum;
755 
756       /* Find the initializer.  */
757       value = (*lang_hooks.tree_inlining.convert_parm_for_inlining)
758 	      (p, a ? TREE_VALUE (a) : NULL_TREE, fn, argnum);
759 
760       /* If the parameter is never assigned to, we may not need to
761 	 create a new variable here at all.  Instead, we may be able
762 	 to just use the argument value.  */
763       if (TREE_READONLY (p)
764 	  && !TREE_ADDRESSABLE (p)
765 	  && value && !TREE_SIDE_EFFECTS (value))
766 	{
767 	  /* Simplify the value, if possible.  */
768 	  value = fold (DECL_P (value) ? decl_constant_value (value) : value);
769 
770 	  /* We can't risk substituting complex expressions.  They
771 	     might contain variables that will be assigned to later.
772 	     Theoretically, we could check the expression to see if
773 	     all of the variables that determine its value are
774 	     read-only, but we don't bother.  */
775 	  if (TREE_CONSTANT (value) || TREE_READONLY_DECL_P (value))
776 	    {
777 	      /* If this is a declaration, wrap it a NOP_EXPR so that
778 		 we don't try to put the VALUE on the list of
779 		 BLOCK_VARS.  */
780 	      if (DECL_P (value))
781 		value = build1 (NOP_EXPR, TREE_TYPE (value), value);
782 
783 	      /* If this is a constant, make sure it has the right type.  */
784 	      else if (TREE_TYPE (value) != TREE_TYPE (p))
785 		value = fold (build1 (NOP_EXPR, TREE_TYPE (p), value));
786 
787 	      splay_tree_insert (id->decl_map,
788 				 (splay_tree_key) p,
789 				 (splay_tree_value) value);
790 	      continue;
791 	    }
792 	}
793 
794       /* Make an equivalent VAR_DECL.  */
795       var = copy_decl_for_inlining (p, fn, VARRAY_TREE (id->fns, 0));
796 
797       /* See if the frontend wants to pass this by invisible reference.  If
798 	 so, our new VAR_DECL will have REFERENCE_TYPE, and we need to
799 	 replace uses of the PARM_DECL with dereferences.  */
800       if (TREE_TYPE (var) != TREE_TYPE (p)
801 	  && POINTER_TYPE_P (TREE_TYPE (var))
802 	  && TREE_TYPE (TREE_TYPE (var)) == TREE_TYPE (p))
803 	var_sub = build1 (INDIRECT_REF, TREE_TYPE (p), var);
804       else
805 	var_sub = var;
806 
807       /* Register the VAR_DECL as the equivalent for the PARM_DECL;
808 	 that way, when the PARM_DECL is encountered, it will be
809 	 automatically replaced by the VAR_DECL.  */
810       splay_tree_insert (id->decl_map,
811 			 (splay_tree_key) p,
812 			 (splay_tree_value) var_sub);
813 
814       /* Declare this new variable.  */
815 #ifndef INLINER_FOR_JAVA
816       init_stmt = build_stmt (DECL_STMT, var);
817       TREE_CHAIN (init_stmt) = init_stmts;
818       init_stmts = init_stmt;
819 #else /* INLINER_FOR_JAVA */
820       TREE_CHAIN (var) = vars;
821       vars = var;
822 #endif /* INLINER_FOR_JAVA */
823 
824       /* Initialize this VAR_DECL from the equivalent argument.  If
825 	 the argument is an object, created via a constructor or copy,
826 	 this will not result in an extra copy: the TARGET_EXPR
827 	 representing the argument will be bound to VAR, and the
828 	 object will be constructed in VAR.  */
829       if (! TYPE_NEEDS_CONSTRUCTING (TREE_TYPE (p)))
830 #ifndef INLINER_FOR_JAVA
831 	DECL_INITIAL (var) = value;
832       else
833 	{
834 	  /* Even if P was TREE_READONLY, the new VAR should not be.
835 	     In the original code, we would have constructed a
836 	     temporary, and then the function body would have never
837 	     changed the value of P.  However, now, we will be
838 	     constructing VAR directly.  The constructor body may
839 	     change its value multiple times as it is being
840 	     constructed.  Therefore, it must not be TREE_READONLY;
841 	     the back-end assumes that TREE_READONLY variable is
842 	     assigned to only once.  */
843 	  TREE_READONLY (var) = 0;
844 
845 	  /* Build a run-time initialization.  */
846 	  init_stmt = build_stmt (EXPR_STMT,
847 				  build (INIT_EXPR, TREE_TYPE (p),
848 					 var, value));
849 	  /* Add this initialization to the list.  Note that we want the
850 	     declaration *after* the initialization because we are going
851 	     to reverse all the initialization statements below.  */
852 	  TREE_CHAIN (init_stmt) = init_stmts;
853 	  init_stmts = init_stmt;
854 	}
855 
856       /* See if we need to clean up the declaration.  */
857       cleanup = (*lang_hooks.maybe_build_cleanup) (var);
858       if (cleanup)
859 	{
860 	  tree cleanup_stmt;
861 	  /* Build the cleanup statement.  */
862 	  cleanup_stmt = build_stmt (CLEANUP_STMT, var, cleanup);
863 	  /* Add it to the *front* of the list; the list will be
864 	     reversed below.  */
865 	  TREE_CHAIN (cleanup_stmt) = init_stmts;
866 	  init_stmts = cleanup_stmt;
867 	}
868 #else /* INLINER_FOR_JAVA */
869 	{
870 	  tree assignment = build (MODIFY_EXPR, TREE_TYPE (p), var, value);
871 	  init_stmts = add_stmt_to_compound (init_stmts, TREE_TYPE (p),
872 					     assignment);
873 	}
874       else
875 	{
876 	  /* Java objects don't ever need constructing when being
877              passed as arguments because only call by reference is
878              supported.  */
879 	  abort ();
880 	}
881 #endif /* INLINER_FOR_JAVA */
882     }
883 
884 #ifndef INLINER_FOR_JAVA
885   /* Evaluate trailing arguments.  */
886   for (; a; a = TREE_CHAIN (a))
887     {
888       tree init_stmt;
889       tree value = TREE_VALUE (a);
890 
891       if (! value || ! TREE_SIDE_EFFECTS (value))
892 	continue;
893 
894       init_stmt = build_stmt (EXPR_STMT, value);
895       TREE_CHAIN (init_stmt) = init_stmts;
896       init_stmts = init_stmt;
897     }
898 
899   /* The initialization statements have been built up in reverse
900      order.  Straighten them out now.  */
901   return nreverse (init_stmts);
902 #else /* INLINER_FOR_JAVA */
903   BLOCK_VARS (block) = nreverse (vars);
904   return init_stmts;
905 #endif /* INLINER_FOR_JAVA */
906 }
907 
908 /* Declare a return variable to replace the RESULT_DECL for the
909    function we are calling.  An appropriate DECL_STMT is returned.
910    The USE_STMT is filled in to contain a use of the declaration to
911    indicate the return value of the function.  */
912 
913 #ifndef INLINER_FOR_JAVA
914 static tree
declare_return_variable(struct inline_data * id,tree return_slot_addr,tree * use_stmt)915 declare_return_variable (struct inline_data *id, tree return_slot_addr,
916 			 tree *use_stmt)
917 #else /* INLINER_FOR_JAVA */
918 static tree
919 declare_return_variable (struct inline_data *id, tree return_slot_addr,
920 			 tree *var)
921 #endif /* INLINER_FOR_JAVA */
922 {
923   tree fn = VARRAY_TOP_TREE (id->fns);
924   tree result = DECL_RESULT (fn);
925 #ifndef INLINER_FOR_JAVA
926   tree var;
927 #endif /* not INLINER_FOR_JAVA */
928   int need_return_decl = 1;
929 
930   /* We don't need to do anything for functions that don't return
931      anything.  */
932   if (!result || VOID_TYPE_P (TREE_TYPE (result)))
933     {
934 #ifndef INLINER_FOR_JAVA
935       *use_stmt = NULL_TREE;
936 #else /* INLINER_FOR_JAVA */
937       *var = NULL_TREE;
938 #endif /* INLINER_FOR_JAVA */
939       return NULL_TREE;
940     }
941 
942 #ifndef INLINER_FOR_JAVA
943   var = ((*lang_hooks.tree_inlining.copy_res_decl_for_inlining)
944 	 (result, fn, VARRAY_TREE (id->fns, 0), id->decl_map,
945 	  &need_return_decl, return_slot_addr));
946 
947   /* Register the VAR_DECL as the equivalent for the RESULT_DECL; that
948      way, when the RESULT_DECL is encountered, it will be
949      automatically replaced by the VAR_DECL.  */
950   splay_tree_insert (id->decl_map,
951 		     (splay_tree_key) result,
952 		     (splay_tree_value) var);
953 
954   /* Build the USE_STMT.  If the return type of the function was
955      promoted, convert it back to the expected type.  */
956   if (TREE_TYPE (var) == TREE_TYPE (TREE_TYPE (fn)))
957     *use_stmt = build_stmt (EXPR_STMT, var);
958   else
959     *use_stmt = build_stmt (EXPR_STMT,
960 			    build1 (NOP_EXPR, TREE_TYPE (TREE_TYPE (fn)),
961 				    var));
962   TREE_ADDRESSABLE (*use_stmt) = 1;
963 
964   /* Build the declaration statement if FN does not return an
965      aggregate.  */
966   if (need_return_decl)
967     return build_stmt (DECL_STMT, var);
968 #else /* INLINER_FOR_JAVA */
969   *var = ((*lang_hooks.tree_inlining.copy_res_decl_for_inlining)
970 	 (result, fn, VARRAY_TREE (id->fns, 0), id->decl_map,
971 	  &need_return_decl, return_slot_addr));
972 
973   splay_tree_insert (id->decl_map,
974 		     (splay_tree_key) result,
975 		     (splay_tree_value) *var);
976   DECL_IGNORED_P (*var) = 1;
977   if (need_return_decl)
978     return *var;
979 #endif /* INLINER_FOR_JAVA */
980   /* If FN does return an aggregate, there's no need to declare the
981      return variable; we're using a variable in our caller's frame.  */
982   else
983     return NULL_TREE;
984 }
985 
986 /* Returns nonzero if a function can be inlined as a tree.  */
987 
988 bool
tree_inlinable_function_p(tree fn)989 tree_inlinable_function_p (tree fn)
990 {
991   return inlinable_function_p (fn);
992 }
993 
994 static const char *inline_forbidden_reason;
995 
996 static tree
inline_forbidden_p_1(tree * nodep,int * walk_subtrees ATTRIBUTE_UNUSED,void * fnp)997 inline_forbidden_p_1 (tree *nodep, int *walk_subtrees ATTRIBUTE_UNUSED,
998 		      void *fnp)
999 {
1000   tree node = *nodep;
1001   tree fn = (tree) fnp;
1002   tree t;
1003 
1004   switch (TREE_CODE (node))
1005     {
1006     case CALL_EXPR:
1007       /* Refuse to inline alloca call unless user explicitly forced so as
1008 	 this may change program's memory overhead drastically when the
1009 	 function using alloca is called in loop.  In GCC present in
1010 	 SPEC2000 inlining into schedule_block cause it to require 2GB of
1011 	 RAM instead of 256MB.  */
1012       if (alloca_call_p (node)
1013 	  && !lookup_attribute ("always_inline", DECL_ATTRIBUTES (fn)))
1014 	{
1015 	  inline_forbidden_reason
1016 	    = N_("%Jfunction '%F' can never be inlined because it uses "
1017 		 "alloca (override using the always_inline attribute)");
1018 	  return node;
1019 	}
1020       t = get_callee_fndecl (node);
1021       if (! t)
1022 	break;
1023 
1024 
1025       /* We cannot inline functions that call setjmp.  */
1026       if (setjmp_call_p (t))
1027 	{
1028 	  inline_forbidden_reason
1029 	    = N_("%Jfunction '%F' can never be inlined because it uses setjmp");
1030 	  return node;
1031 	}
1032 
1033       if (DECL_BUILT_IN (t))
1034 	switch (DECL_FUNCTION_CODE (t))
1035 	  {
1036 	    /* We cannot inline functions that take a variable number of
1037 	       arguments.  */
1038 	  case BUILT_IN_VA_START:
1039 	  case BUILT_IN_STDARG_START:
1040 	  case BUILT_IN_NEXT_ARG:
1041 	  case BUILT_IN_VA_END:
1042 	    {
1043 	      inline_forbidden_reason
1044 		= N_("%Jfunction '%F' can never be inlined because it "
1045 		     "uses variable argument lists");
1046 	      return node;
1047 	    }
1048 	  case BUILT_IN_LONGJMP:
1049 	    {
1050 	      /* We can't inline functions that call __builtin_longjmp at
1051 		 all.  The non-local goto machinery really requires the
1052 		 destination be in a different function.  If we allow the
1053 		 function calling __builtin_longjmp to be inlined into the
1054 		 function calling __builtin_setjmp, Things will Go Awry.  */
1055 	      /* ??? Need front end help to identify "regular" non-local
1056 		 goto.  */
1057 	      if (DECL_BUILT_IN_CLASS (t) == BUILT_IN_NORMAL)
1058 		{
1059 		  inline_forbidden_reason
1060 		    = N_("%Jfunction '%F' can never be inlined because "
1061 			 "it uses setjmp-longjmp exception handling");
1062 		  return node;
1063 		}
1064 	    }
1065 
1066 	  default:
1067 	    break;
1068 	  }
1069       break;
1070 
1071 #ifndef INLINER_FOR_JAVA
1072     case DECL_STMT:
1073       /* We cannot inline functions that contain other functions.  */
1074       if (TREE_CODE (TREE_OPERAND (node, 0)) == FUNCTION_DECL
1075 	  && DECL_INITIAL (TREE_OPERAND (node, 0)))
1076 	{
1077 	  inline_forbidden_reason
1078 	    = N_("%Jfunction '%F' can never be inlined "
1079 		 "because it contains a nested function");
1080 	  return node;
1081 	}
1082       break;
1083 
1084     case GOTO_STMT:
1085     case GOTO_EXPR:
1086       t = TREE_OPERAND (node, 0);
1087 
1088       /* We will not inline a function which uses computed goto.  The
1089 	 addresses of its local labels, which may be tucked into
1090 	 global storage, are of course not constant across
1091 	 instantiations, which causes unexpected behavior.  */
1092       if (TREE_CODE (t) != LABEL_DECL)
1093 	{
1094 	  inline_forbidden_reason
1095 	    = N_("%Jfunction '%F' can never be inlined "
1096 		 "because it contains a computed goto");
1097 	  return node;
1098 	}
1099 
1100       /* We cannot inline a nested function that jumps to a nonlocal
1101          label.  */
1102       if (TREE_CODE (t) == LABEL_DECL && DECL_CONTEXT (t) != fn)
1103 	{
1104 	  inline_forbidden_reason
1105 	    = N_("%Jfunction '%F' can never be inlined "
1106 		 "because it contains a nonlocal goto");
1107 	  return node;
1108 	}
1109 
1110       break;
1111 
1112     case RECORD_TYPE:
1113     case UNION_TYPE:
1114       /* We cannot inline a function of the form
1115 
1116 	   void F (int i) { struct S { int ar[i]; } s; }
1117 
1118 	 Attempting to do so produces a catch-22.
1119 	 If walk_tree examines the TYPE_FIELDS chain of RECORD_TYPE/
1120 	 UNION_TYPE nodes, then it goes into infinite recursion on a
1121 	 structure containing a pointer to its own type.  If it doesn't,
1122 	 then the type node for S doesn't get adjusted properly when
1123 	 F is inlined, and we abort in find_function_data.  */
1124       for (t = TYPE_FIELDS (node); t; t = TREE_CHAIN (t))
1125 	if (variably_modified_type_p (TREE_TYPE (t)))
1126 	  {
1127 	    inline_forbidden_reason
1128 	      = N_("%Jfunction '%F' can never be inlined "
1129 		   "because it uses variable sized variables");
1130 	    return node;
1131 	  }
1132 #endif
1133     default:
1134       break;
1135     }
1136 
1137   return NULL_TREE;
1138 }
1139 
1140 /* Return subexpression representing possible alloca call, if any.  */
1141 static tree
inline_forbidden_p(tree fndecl)1142 inline_forbidden_p (tree fndecl)
1143 {
1144   location_t saved_loc = input_location;
1145   tree ret = walk_tree_without_duplicates
1146 		(&DECL_SAVED_TREE (fndecl), inline_forbidden_p_1, fndecl);
1147   input_location = saved_loc;
1148   return ret;
1149 }
1150 
1151 /* Returns nonzero if FN is a function that does not have any
1152    fundamental inline blocking properties.  */
1153 
1154 static bool
inlinable_function_p(tree fn)1155 inlinable_function_p (tree fn)
1156 {
1157   bool inlinable = true;
1158 
1159   /* If we've already decided this function shouldn't be inlined,
1160      there's no need to check again.  */
1161   if (DECL_UNINLINABLE (fn))
1162     return false;
1163 
1164   /* See if there is any language-specific reason it cannot be
1165      inlined.  (It is important that this hook be called early because
1166      in C++ it may result in template instantiation.)
1167      If the function is not inlinable for language-specific reasons,
1168      it is left up to the langhook to explain why.  */
1169   inlinable = !(*lang_hooks.tree_inlining.cannot_inline_tree_fn) (&fn);
1170 
1171   /* If we don't have the function body available, we can't inline it.
1172      However, this should not be recorded since we also get here for
1173      forward declared inline functions.  Therefore, return at once.  */
1174   if (!DECL_SAVED_TREE (fn))
1175     return false;
1176 
1177   /* If we're not inlining at all, then we cannot inline this function.  */
1178   else if (!flag_inline_trees)
1179     inlinable = false;
1180 
1181   /* Only try to inline functions if DECL_INLINE is set.  This should be
1182      true for all functions declared `inline', and for all other functions
1183      as well with -finline-functions.
1184 
1185      Don't think of disregarding DECL_INLINE when flag_inline_trees == 2;
1186      it's the front-end that must set DECL_INLINE in this case, because
1187      dwarf2out loses if a function that does not have DECL_INLINE set is
1188      inlined anyway.  That is why we have both DECL_INLINE and
1189      DECL_DECLARED_INLINE_P.  */
1190   /* FIXME: When flag_inline_trees dies, the check for flag_unit_at_a_time
1191 	    here should be redundant.  */
1192   else if (!DECL_INLINE (fn) && !flag_unit_at_a_time)
1193     inlinable = false;
1194 
1195 #ifdef INLINER_FOR_JAVA
1196   /* Synchronized methods can't be inlined.  This is a bug.  */
1197   else if (METHOD_SYNCHRONIZED (fn))
1198     inlinable = false;
1199 #endif /* INLINER_FOR_JAVA */
1200 
1201   else if (inline_forbidden_p (fn))
1202     {
1203       /* See if we should warn about uninlinable functions.  Previously,
1204 	 some of these warnings would be issued while trying to expand
1205 	 the function inline, but that would cause multiple warnings
1206 	 about functions that would for example call alloca.  But since
1207 	 this a property of the function, just one warning is enough.
1208 	 As a bonus we can now give more details about the reason why a
1209 	 function is not inlinable.
1210 	 We only warn for functions declared `inline' by the user.  */
1211       bool do_warning = (warn_inline
1212 			 && DECL_INLINE (fn)
1213 			 && DECL_DECLARED_INLINE_P (fn)
1214 			 && !DECL_IN_SYSTEM_HEADER (fn));
1215 
1216       if (lookup_attribute ("always_inline",
1217 			    DECL_ATTRIBUTES (fn)))
1218 	sorry (inline_forbidden_reason, fn, fn);
1219       else if (do_warning)
1220 	warning (inline_forbidden_reason, fn, fn);
1221 
1222       inlinable = false;
1223     }
1224 
1225   /* Squirrel away the result so that we don't have to check again.  */
1226   DECL_UNINLINABLE (fn) = !inlinable;
1227 
1228   return inlinable;
1229 }
1230 
1231 /* If *TP is a CALL_EXPR, replace it with its inline expansion.  */
1232 
1233 static tree
expand_call_inline(tree * tp,int * walk_subtrees,void * data)1234 expand_call_inline (tree *tp, int *walk_subtrees, void *data)
1235 {
1236   inline_data *id;
1237   tree t;
1238   tree expr;
1239   tree stmt;
1240 #ifndef INLINER_FOR_JAVA
1241   tree chain;
1242   tree scope_stmt;
1243   tree use_stmt;
1244 #else /* INLINER_FOR_JAVA */
1245   tree retvar;
1246 #endif /* INLINER_FOR_JAVA */
1247   tree fn;
1248   tree arg_inits;
1249   tree *inlined_body;
1250   splay_tree st;
1251   tree args;
1252   tree return_slot_addr;
1253   const char *reason;
1254 
1255   /* See what we've got.  */
1256   id = (inline_data *) data;
1257   t = *tp;
1258 
1259   /* Recurse, but letting recursive invocations know that we are
1260      inside the body of a TARGET_EXPR.  */
1261   if (TREE_CODE (*tp) == TARGET_EXPR)
1262     {
1263 #ifndef INLINER_FOR_JAVA
1264       int i, len = first_rtl_op (TARGET_EXPR);
1265 
1266       /* We're walking our own subtrees.  */
1267       *walk_subtrees = 0;
1268 
1269       /* Actually walk over them.  This loop is the body of
1270 	 walk_trees, omitting the case where the TARGET_EXPR
1271 	 itself is handled.  */
1272       for (i = 0; i < len; ++i)
1273 	{
1274 	  if (i == 2)
1275 	    ++id->in_target_cleanup_p;
1276 	  walk_tree (&TREE_OPERAND (*tp, i), expand_call_inline, data,
1277 		     id->tree_pruner);
1278 	  if (i == 2)
1279 	    --id->in_target_cleanup_p;
1280 	}
1281 
1282       return NULL_TREE;
1283 #else /* INLINER_FOR_JAVA */
1284       abort ();
1285 #endif /* INLINER_FOR_JAVA */
1286     }
1287   else if (TREE_CODE (t) == EXPR_WITH_FILE_LOCATION)
1288     {
1289       /* We're walking the subtree directly.  */
1290       *walk_subtrees = 0;
1291       /* Update the source position.  */
1292       push_srcloc (EXPR_WFL_FILENAME (t), EXPR_WFL_LINENO (t));
1293       walk_tree (&EXPR_WFL_NODE (t), expand_call_inline, data,
1294 		 id->tree_pruner);
1295       /* Restore the original source position.  */
1296       pop_srcloc ();
1297 
1298       return NULL_TREE;
1299     }
1300 
1301   if (TYPE_P (t))
1302     /* Because types were not copied in copy_body, CALL_EXPRs beneath
1303        them should not be expanded.  This can happen if the type is a
1304        dynamic array type, for example.  */
1305     *walk_subtrees = 0;
1306 
1307   /* From here on, we're only interested in CALL_EXPRs.  */
1308   if (TREE_CODE (t) != CALL_EXPR)
1309     return NULL_TREE;
1310 
1311   /* First, see if we can figure out what function is being called.
1312      If we cannot, then there is no hope of inlining the function.  */
1313   fn = get_callee_fndecl (t);
1314   if (!fn)
1315     return NULL_TREE;
1316 
1317   /* Turn forward declarations into real ones.  */
1318   fn = cgraph_node (fn)->decl;
1319 
1320   /* If fn is a declaration of a function in a nested scope that was
1321      globally declared inline, we don't set its DECL_INITIAL.
1322      However, we can't blindly follow DECL_ABSTRACT_ORIGIN because the
1323      C++ front-end uses it for cdtors to refer to their internal
1324      declarations, that are not real functions.  Fortunately those
1325      don't have trees to be saved, so we can tell by checking their
1326      DECL_SAVED_TREE.  */
1327   if (! DECL_INITIAL (fn)
1328       && DECL_ABSTRACT_ORIGIN (fn)
1329       && DECL_SAVED_TREE (DECL_ABSTRACT_ORIGIN (fn)))
1330     fn = DECL_ABSTRACT_ORIGIN (fn);
1331 
1332   /* Don't try to inline functions that are not well-suited to
1333      inlining.  */
1334   if (!cgraph_inline_p (id->current_decl, fn, &reason))
1335     {
1336       if (lookup_attribute ("always_inline", DECL_ATTRIBUTES (fn)))
1337 	{
1338 	  sorry ("%Jinlining failed in call to '%F': %s", fn, fn, reason);
1339 	  sorry ("called from here");
1340 	}
1341       else if (warn_inline && DECL_DECLARED_INLINE_P (fn)
1342 	       && !DECL_IN_SYSTEM_HEADER (fn)
1343 	       && strlen (reason))
1344 	{
1345 	  warning ("%Jinlining failed in call to '%F': %s", fn, fn, reason);
1346 	  warning ("called from here");
1347 	}
1348       return NULL_TREE;
1349     }
1350 
1351   if (! (*lang_hooks.tree_inlining.start_inlining) (fn))
1352     return NULL_TREE;
1353 
1354   /* Set the current filename and line number to the function we are
1355      inlining so that when we create new _STMT nodes here they get
1356      line numbers corresponding to the function we are calling.  We
1357      wrap the whole inlined body in an EXPR_WITH_FILE_AND_LINE as well
1358      because individual statements don't record the filename.  */
1359   push_srcloc (DECL_SOURCE_FILE (fn), DECL_SOURCE_LINE (fn));
1360 
1361 #ifndef INLINER_FOR_JAVA
1362   /* Build a statement-expression containing code to initialize the
1363      arguments, the actual inline expansion of the body, and a label
1364      for the return statements within the function to jump to.  The
1365      type of the statement expression is the return type of the
1366      function call.  */
1367   expr = build1 (STMT_EXPR, TREE_TYPE (TREE_TYPE (fn)), make_node (COMPOUND_STMT));
1368   /* There is no scope associated with the statement-expression.  */
1369   STMT_EXPR_NO_SCOPE (expr) = 1;
1370   if (lookup_attribute ("warn_unused_result",
1371 			TYPE_ATTRIBUTES (TREE_TYPE (fn))))
1372     STMT_EXPR_WARN_UNUSED_RESULT (expr) = 1;
1373   stmt = STMT_EXPR_STMT (expr);
1374 #else /* INLINER_FOR_JAVA */
1375   /* Build a block containing code to initialize the arguments, the
1376      actual inline expansion of the body, and a label for the return
1377      statements within the function to jump to.  The type of the
1378      statement expression is the return type of the function call.  */
1379   stmt = NULL;
1380   expr = build (BLOCK, TREE_TYPE (TREE_TYPE (fn)), stmt);
1381 #endif /* INLINER_FOR_JAVA */
1382 
1383   /* Local declarations will be replaced by their equivalents in this
1384      map.  */
1385   st = id->decl_map;
1386   id->decl_map = splay_tree_new (splay_tree_compare_pointers,
1387 				 NULL, NULL);
1388 
1389   /* Initialize the parameters.  */
1390   args = TREE_OPERAND (t, 1);
1391   return_slot_addr = NULL_TREE;
1392   if (CALL_EXPR_HAS_RETURN_SLOT_ADDR (t))
1393     {
1394       return_slot_addr = TREE_VALUE (args);
1395       args = TREE_CHAIN (args);
1396     }
1397 
1398 #ifndef INLINER_FOR_JAVA
1399   arg_inits = initialize_inlined_parameters (id, args, fn);
1400   /* Expand any inlined calls in the initializers.  Do this before we
1401      push FN on the stack of functions we are inlining; we want to
1402      inline calls to FN that appear in the initializers for the
1403      parameters.  */
1404   expand_calls_inline (&arg_inits, id);
1405   /* And add them to the tree.  */
1406   COMPOUND_BODY (stmt) = chainon (COMPOUND_BODY (stmt), arg_inits);
1407 #else /* INLINER_FOR_JAVA */
1408   arg_inits = initialize_inlined_parameters (id, args, fn, expr);
1409   if (arg_inits)
1410     {
1411       /* Expand any inlined calls in the initializers.  Do this before we
1412 	 push FN on the stack of functions we are inlining; we want to
1413 	 inline calls to FN that appear in the initializers for the
1414 	 parameters.  */
1415       expand_calls_inline (&arg_inits, id);
1416 
1417       /* And add them to the tree.  */
1418       BLOCK_EXPR_BODY (expr) = add_stmt_to_compound (BLOCK_EXPR_BODY (expr),
1419 						     TREE_TYPE (arg_inits),
1420 						     arg_inits);
1421     }
1422 #endif /* INLINER_FOR_JAVA */
1423 
1424   /* Record the function we are about to inline so that we can avoid
1425      recursing into it.  */
1426   VARRAY_PUSH_TREE (id->fns, fn);
1427 
1428   /* Record the function we are about to inline if optimize_function
1429      has not been called on it yet and we don't have it in the list.  */
1430   if (! DECL_INLINED_FNS (fn))
1431     {
1432       int i;
1433 
1434       for (i = VARRAY_ACTIVE_SIZE (id->inlined_fns) - 1; i >= 0; i--)
1435 	if (VARRAY_TREE (id->inlined_fns, i) == fn)
1436 	  break;
1437       if (i < 0)
1438 	VARRAY_PUSH_TREE (id->inlined_fns, fn);
1439     }
1440 
1441   /* Return statements in the function body will be replaced by jumps
1442      to the RET_LABEL.  */
1443   id->ret_label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE);
1444   DECL_CONTEXT (id->ret_label) = VARRAY_TREE (id->fns, 0);
1445 
1446   if (! DECL_INITIAL (fn)
1447       || TREE_CODE (DECL_INITIAL (fn)) != BLOCK)
1448     abort ();
1449 
1450 #ifndef INLINER_FOR_JAVA
1451   /* Create a block to put the parameters in.  We have to do this
1452      after the parameters have been remapped because remapping
1453      parameters is different from remapping ordinary variables.  */
1454   scope_stmt = build_stmt (SCOPE_STMT, DECL_INITIAL (fn));
1455   SCOPE_BEGIN_P (scope_stmt) = 1;
1456   SCOPE_NO_CLEANUPS_P (scope_stmt) = 1;
1457   remap_block (scope_stmt, DECL_ARGUMENTS (fn), id);
1458   TREE_CHAIN (scope_stmt) = COMPOUND_BODY (stmt);
1459   COMPOUND_BODY (stmt) = scope_stmt;
1460 
1461   /* Tell the debugging backends that this block represents the
1462      outermost scope of the inlined function.  */
1463   if (SCOPE_STMT_BLOCK (scope_stmt))
1464     BLOCK_ABSTRACT_ORIGIN (SCOPE_STMT_BLOCK (scope_stmt)) = DECL_ORIGIN (fn);
1465 
1466   /* Declare the return variable for the function.  */
1467   COMPOUND_BODY (stmt)
1468     = chainon (COMPOUND_BODY (stmt),
1469 	       declare_return_variable (id, return_slot_addr, &use_stmt));
1470 #else /* INLINER_FOR_JAVA */
1471   {
1472     /* Declare the return variable for the function.  */
1473     tree decl = declare_return_variable (id, return_slot_addr, &retvar);
1474     if (retvar)
1475       {
1476 	tree *next = &BLOCK_VARS (expr);
1477 	while (*next)
1478 	  next = &TREE_CHAIN (*next);
1479 	*next = decl;
1480       }
1481   }
1482 #endif /* INLINER_FOR_JAVA */
1483 
1484   /* After we've initialized the parameters, we insert the body of the
1485      function itself.  */
1486 #ifndef INLINER_FOR_JAVA
1487   inlined_body = &COMPOUND_BODY (stmt);
1488   while (*inlined_body)
1489     inlined_body = &TREE_CHAIN (*inlined_body);
1490   *inlined_body = copy_body (id);
1491 #else /* INLINER_FOR_JAVA */
1492   {
1493     tree new_body;
1494     java_inlining_map_static_initializers (fn, id->decl_map);
1495     new_body = copy_body (id);
1496     TREE_TYPE (new_body) = TREE_TYPE (TREE_TYPE (fn));
1497     BLOCK_EXPR_BODY (expr)
1498       = add_stmt_to_compound (BLOCK_EXPR_BODY (expr),
1499 			      TREE_TYPE (new_body), new_body);
1500     inlined_body = &BLOCK_EXPR_BODY (expr);
1501   }
1502 #endif /* INLINER_FOR_JAVA */
1503 
1504   /* After the body of the function comes the RET_LABEL.  This must come
1505      before we evaluate the returned value below, because that evaluation
1506      may cause RTL to be generated.  */
1507 #ifndef INLINER_FOR_JAVA
1508   COMPOUND_BODY (stmt)
1509     = chainon (COMPOUND_BODY (stmt),
1510 	       build_stmt (LABEL_STMT, id->ret_label));
1511 #else /* INLINER_FOR_JAVA */
1512   {
1513     tree label = build1 (LABEL_EXPR, void_type_node, id->ret_label);
1514     BLOCK_EXPR_BODY (expr)
1515       = add_stmt_to_compound (BLOCK_EXPR_BODY (expr), void_type_node, label);
1516     TREE_SIDE_EFFECTS (label) = TREE_SIDE_EFFECTS (t);
1517   }
1518 #endif /* INLINER_FOR_JAVA */
1519 
1520   /* Finally, mention the returned value so that the value of the
1521      statement-expression is the returned value of the function.  */
1522 #ifndef INLINER_FOR_JAVA
1523   COMPOUND_BODY (stmt) = chainon (COMPOUND_BODY (stmt), use_stmt);
1524 
1525   /* Close the block for the parameters.  */
1526   scope_stmt = build_stmt (SCOPE_STMT, DECL_INITIAL (fn));
1527   SCOPE_NO_CLEANUPS_P (scope_stmt) = 1;
1528   remap_block (scope_stmt, NULL_TREE, id);
1529   COMPOUND_BODY (stmt)
1530     = chainon (COMPOUND_BODY (stmt), scope_stmt);
1531 #else /* INLINER_FOR_JAVA */
1532   if (retvar)
1533     {
1534       /* Mention the retvar.  If the return type of the function was
1535 	 promoted, convert it back to the expected type.  */
1536       if (TREE_TYPE (TREE_TYPE (fn)) != TREE_TYPE (retvar))
1537 	retvar = build1 (NOP_EXPR, TREE_TYPE (TREE_TYPE (fn)), retvar);
1538       BLOCK_EXPR_BODY (expr)
1539 	= add_stmt_to_compound (BLOCK_EXPR_BODY (expr),
1540 				TREE_TYPE (retvar), retvar);
1541     }
1542 
1543   java_inlining_merge_static_initializers (fn, id->decl_map);
1544 #endif /* INLINER_FOR_JAVA */
1545 
1546   /* Clean up.  */
1547   splay_tree_delete (id->decl_map);
1548   id->decl_map = st;
1549 
1550   /* The new expression has side-effects if the old one did.  */
1551   TREE_SIDE_EFFECTS (expr) = TREE_SIDE_EFFECTS (t);
1552 
1553   /* Replace the call by the inlined body.  Wrap it in an
1554      EXPR_WITH_FILE_LOCATION so that we'll get debugging line notes
1555      pointing to the right place.  */
1556 #ifndef INLINER_FOR_JAVA
1557   chain = TREE_CHAIN (*tp);
1558 #endif /* INLINER_FOR_JAVA */
1559   *tp = build_expr_wfl (expr, DECL_SOURCE_FILE (fn), DECL_SOURCE_LINE (fn),
1560 			/*col=*/0);
1561   EXPR_WFL_EMIT_LINE_NOTE (*tp) = 1;
1562 #ifndef INLINER_FOR_JAVA
1563   TREE_CHAIN (*tp) = chain;
1564 #endif /* not INLINER_FOR_JAVA */
1565   pop_srcloc ();
1566 
1567   /* If the value of the new expression is ignored, that's OK.  We
1568      don't warn about this for CALL_EXPRs, so we shouldn't warn about
1569      the equivalent inlined version either.  */
1570   TREE_USED (*tp) = 1;
1571 
1572   /* Update callgraph if needed.  */
1573   if (id->decl)
1574     {
1575       cgraph_remove_call (id->decl, fn);
1576       cgraph_create_edges (id->decl, *inlined_body);
1577     }
1578 
1579   /* Recurse into the body of the just inlined function.  */
1580   {
1581     tree old_decl = id->current_decl;
1582     id->current_decl = fn;
1583     expand_calls_inline (inlined_body, id);
1584     id->current_decl = old_decl;
1585   }
1586   VARRAY_POP (id->fns);
1587 
1588   /* Don't walk into subtrees.  We've already handled them above.  */
1589   *walk_subtrees = 0;
1590 
1591   (*lang_hooks.tree_inlining.end_inlining) (fn);
1592 
1593   /* Keep iterating.  */
1594   return NULL_TREE;
1595 }
1596 /* Walk over the entire tree *TP, replacing CALL_EXPRs with inline
1597    expansions as appropriate.  */
1598 
1599 static void
expand_calls_inline(tree * tp,inline_data * id)1600 expand_calls_inline (tree *tp, inline_data *id)
1601 {
1602   /* Search through *TP, replacing all calls to inline functions by
1603      appropriate equivalents.  Use walk_tree in no-duplicates mode
1604      to avoid exponential time complexity.  (We can't just use
1605      walk_tree_without_duplicates, because of the special TARGET_EXPR
1606      handling in expand_calls.  The hash table is set up in
1607      optimize_function.  */
1608   walk_tree (tp, expand_call_inline, id, id->tree_pruner);
1609 }
1610 
1611 /* Expand calls to inline functions in the body of FN.  */
1612 
1613 void
optimize_inline_calls(tree fn)1614 optimize_inline_calls (tree fn)
1615 {
1616   inline_data id;
1617   tree prev_fn;
1618 
1619   /* There is no point in performing inlining if errors have already
1620      occurred -- and we might crash if we try to inline invalid
1621      code.  */
1622   if (errorcount || sorrycount)
1623     return;
1624 
1625   /* Clear out ID.  */
1626   memset (&id, 0, sizeof (id));
1627 
1628   id.decl = fn;
1629   id.current_decl = fn;
1630   /* Don't allow recursion into FN.  */
1631   VARRAY_TREE_INIT (id.fns, 32, "fns");
1632   VARRAY_PUSH_TREE (id.fns, fn);
1633   /* Or any functions that aren't finished yet.  */
1634   prev_fn = NULL_TREE;
1635   if (current_function_decl)
1636     {
1637       VARRAY_PUSH_TREE (id.fns, current_function_decl);
1638       prev_fn = current_function_decl;
1639     }
1640 
1641   prev_fn = ((*lang_hooks.tree_inlining.add_pending_fn_decls)
1642 	     (&id.fns, prev_fn));
1643 
1644   /* Create the list of functions this call will inline.  */
1645   VARRAY_TREE_INIT (id.inlined_fns, 32, "inlined_fns");
1646 
1647   /* Keep track of the low-water mark, i.e., the point where the first
1648      real inlining is represented in ID.FNS.  */
1649   id.first_inlined_fn = VARRAY_ACTIVE_SIZE (id.fns);
1650 
1651   /* Replace all calls to inline functions with the bodies of those
1652      functions.  */
1653   id.tree_pruner = htab_create (37, htab_hash_pointer,
1654 				htab_eq_pointer, NULL);
1655   expand_calls_inline (&DECL_SAVED_TREE (fn), &id);
1656 
1657   /* Clean up.  */
1658   htab_delete (id.tree_pruner);
1659   if (DECL_LANG_SPECIFIC (fn))
1660     {
1661       tree ifn = make_tree_vec (VARRAY_ACTIVE_SIZE (id.inlined_fns));
1662 
1663       if (VARRAY_ACTIVE_SIZE (id.inlined_fns))
1664 	memcpy (&TREE_VEC_ELT (ifn, 0), &VARRAY_TREE (id.inlined_fns, 0),
1665 		VARRAY_ACTIVE_SIZE (id.inlined_fns) * sizeof (tree));
1666       DECL_INLINED_FNS (fn) = ifn;
1667     }
1668 }
1669 
1670 /* FN is a function that has a complete body, and CLONE is a function
1671    whose body is to be set to a copy of FN, mapping argument
1672    declarations according to the ARG_MAP splay_tree.  */
1673 
1674 void
clone_body(tree clone,tree fn,void * arg_map)1675 clone_body (tree clone, tree fn, void *arg_map)
1676 {
1677   inline_data id;
1678 
1679   /* Clone the body, as if we were making an inline call.  But, remap
1680      the parameters in the callee to the parameters of caller.  If
1681      there's an in-charge parameter, map it to an appropriate
1682      constant.  */
1683   memset (&id, 0, sizeof (id));
1684   VARRAY_TREE_INIT (id.fns, 2, "fns");
1685   VARRAY_PUSH_TREE (id.fns, clone);
1686   VARRAY_PUSH_TREE (id.fns, fn);
1687   id.decl_map = (splay_tree)arg_map;
1688 
1689   /* Cloning is treated slightly differently from inlining.  Set
1690      CLONING_P so that it's clear which operation we're performing.  */
1691   id.cloning_p = true;
1692 
1693   /* Actually copy the body.  */
1694   TREE_CHAIN (DECL_SAVED_TREE (clone)) = copy_body (&id);
1695 }
1696 
1697 /* Apply FUNC to all the sub-trees of TP in a pre-order traversal.
1698    FUNC is called with the DATA and the address of each sub-tree.  If
1699    FUNC returns a non-NULL value, the traversal is aborted, and the
1700    value returned by FUNC is returned.  If HTAB is non-NULL it is used
1701    to record the nodes visited, and to avoid visiting a node more than
1702    once.  */
1703 
1704 tree
walk_tree(tree * tp,walk_tree_fn func,void * data,void * htab_)1705 walk_tree (tree *tp, walk_tree_fn func, void *data, void *htab_)
1706 {
1707   htab_t htab = (htab_t) htab_;
1708   enum tree_code code;
1709   int walk_subtrees;
1710   tree result;
1711 
1712 #define WALK_SUBTREE(NODE)				\
1713   do							\
1714     {							\
1715       result = walk_tree (&(NODE), func, data, htab);	\
1716       if (result)					\
1717 	return result;					\
1718     }							\
1719   while (0)
1720 
1721 #define WALK_SUBTREE_TAIL(NODE)				\
1722   do							\
1723     {							\
1724        tp = & (NODE);					\
1725        goto tail_recurse;				\
1726     }							\
1727   while (0)
1728 
1729  tail_recurse:
1730   /* Skip empty subtrees.  */
1731   if (!*tp)
1732     return NULL_TREE;
1733 
1734   if (htab)
1735     {
1736       void **slot;
1737 
1738       /* Don't walk the same tree twice, if the user has requested
1739          that we avoid doing so.  */
1740       slot = htab_find_slot (htab, *tp, INSERT);
1741       if (*slot)
1742 	return NULL_TREE;
1743       *slot = *tp;
1744     }
1745 
1746   /* Call the function.  */
1747   walk_subtrees = 1;
1748   result = (*func) (tp, &walk_subtrees, data);
1749 
1750   /* If we found something, return it.  */
1751   if (result)
1752     return result;
1753 
1754   code = TREE_CODE (*tp);
1755 
1756 #ifndef INLINER_FOR_JAVA
1757   /* Even if we didn't, FUNC may have decided that there was nothing
1758      interesting below this point in the tree.  */
1759   if (!walk_subtrees)
1760     {
1761       if (STATEMENT_CODE_P (code) || code == TREE_LIST
1762 	  || (*lang_hooks.tree_inlining.tree_chain_matters_p) (*tp))
1763 	/* But we still need to check our siblings.  */
1764 	WALK_SUBTREE_TAIL (TREE_CHAIN (*tp));
1765       else
1766 	return NULL_TREE;
1767     }
1768 
1769   /* Handle common cases up front.  */
1770   if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
1771 #else /* INLINER_FOR_JAVA */
1772   if (code != EXIT_BLOCK_EXPR
1773       && code != SAVE_EXPR
1774       && IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code)))
1775 #endif /* INLINER_FOR_JAVA */
1776     {
1777       int i, len;
1778 
1779 #ifndef INLINER_FOR_JAVA
1780       /* Set lineno here so we get the right instantiation context
1781 	 if we call instantiate_decl from inlinable_function_p.  */
1782       if (STATEMENT_CODE_P (code) && !STMT_LINENO_FOR_FN_P (*tp))
1783 	input_line = STMT_LINENO (*tp);
1784 #endif /* not INLINER_FOR_JAVA */
1785 
1786       /* Walk over all the sub-trees of this operand.  */
1787       len = first_rtl_op (code);
1788       /* TARGET_EXPRs are peculiar: operands 1 and 3 can be the same.
1789 	 But, we only want to walk once.  */
1790       if (code == TARGET_EXPR
1791 	  && TREE_OPERAND (*tp, 3) == TREE_OPERAND (*tp, 1))
1792 	--len;
1793       /* Go through the subtrees.  We need to do this in forward order so
1794          that the scope of a FOR_EXPR is handled properly.  */
1795       for (i = 0; i < len; ++i)
1796 	WALK_SUBTREE (TREE_OPERAND (*tp, i));
1797 
1798 #ifndef INLINER_FOR_JAVA
1799       /* For statements, we also walk the chain so that we cover the
1800 	 entire statement tree.  */
1801       if (STATEMENT_CODE_P (code))
1802 	{
1803 	  if (code == DECL_STMT
1804 	      && DECL_STMT_DECL (*tp)
1805 	      && DECL_P (DECL_STMT_DECL (*tp)))
1806 	    {
1807 	      /* Walk the DECL_INITIAL and DECL_SIZE.  We don't want to walk
1808 		 into declarations that are just mentioned, rather than
1809 		 declared; they don't really belong to this part of the tree.
1810 		 And, we can see cycles: the initializer for a declaration can
1811 		 refer to the declaration itself.  */
1812 	      WALK_SUBTREE (DECL_INITIAL (DECL_STMT_DECL (*tp)));
1813 	      WALK_SUBTREE (DECL_SIZE (DECL_STMT_DECL (*tp)));
1814 	      WALK_SUBTREE (DECL_SIZE_UNIT (DECL_STMT_DECL (*tp)));
1815 	      WALK_SUBTREE (TREE_TYPE (*tp));
1816 	    }
1817 
1818 	  /* This can be tail-recursion optimized if we write it this way.  */
1819 	  WALK_SUBTREE_TAIL (TREE_CHAIN (*tp));
1820 	}
1821 
1822 #endif /* not INLINER_FOR_JAVA */
1823       /* We didn't find what we were looking for.  */
1824       return NULL_TREE;
1825     }
1826   else if (TREE_CODE_CLASS (code) == 'd')
1827     {
1828       WALK_SUBTREE_TAIL (TREE_TYPE (*tp));
1829     }
1830   else if (TREE_CODE_CLASS (code) == 't')
1831     {
1832       WALK_SUBTREE (TYPE_SIZE (*tp));
1833       WALK_SUBTREE (TYPE_SIZE_UNIT (*tp));
1834       /* Also examine various special fields, below.  */
1835     }
1836 
1837   result = (*lang_hooks.tree_inlining.walk_subtrees) (tp, &walk_subtrees, func,
1838 						      data, htab);
1839   if (result || ! walk_subtrees)
1840     return result;
1841 
1842   /* Not one of the easy cases.  We must explicitly go through the
1843      children.  */
1844   switch (code)
1845     {
1846     case ERROR_MARK:
1847     case IDENTIFIER_NODE:
1848     case INTEGER_CST:
1849     case REAL_CST:
1850     case VECTOR_CST:
1851     case STRING_CST:
1852     case REAL_TYPE:
1853     case COMPLEX_TYPE:
1854     case VECTOR_TYPE:
1855     case VOID_TYPE:
1856     case BOOLEAN_TYPE:
1857     case UNION_TYPE:
1858     case ENUMERAL_TYPE:
1859     case BLOCK:
1860     case RECORD_TYPE:
1861     case CHAR_TYPE:
1862     case PLACEHOLDER_EXPR:
1863       /* None of these have subtrees other than those already walked
1864          above.  */
1865       break;
1866 
1867     case POINTER_TYPE:
1868     case REFERENCE_TYPE:
1869       WALK_SUBTREE_TAIL (TREE_TYPE (*tp));
1870       break;
1871 
1872     case TREE_LIST:
1873       WALK_SUBTREE (TREE_VALUE (*tp));
1874       WALK_SUBTREE_TAIL (TREE_CHAIN (*tp));
1875       break;
1876 
1877     case TREE_VEC:
1878       {
1879 	int len = TREE_VEC_LENGTH (*tp);
1880 
1881 	if (len == 0)
1882 	  break;
1883 
1884 	/* Walk all elements but the first.  */
1885 	while (--len)
1886 	  WALK_SUBTREE (TREE_VEC_ELT (*tp, len));
1887 
1888 	/* Now walk the first one as a tail call.  */
1889 	WALK_SUBTREE_TAIL (TREE_VEC_ELT (*tp, 0));
1890       }
1891 
1892     case COMPLEX_CST:
1893       WALK_SUBTREE (TREE_REALPART (*tp));
1894       WALK_SUBTREE_TAIL (TREE_IMAGPART (*tp));
1895 
1896     case CONSTRUCTOR:
1897       WALK_SUBTREE_TAIL (CONSTRUCTOR_ELTS (*tp));
1898 
1899     case METHOD_TYPE:
1900       WALK_SUBTREE (TYPE_METHOD_BASETYPE (*tp));
1901       /* Fall through.  */
1902 
1903     case FUNCTION_TYPE:
1904       WALK_SUBTREE (TREE_TYPE (*tp));
1905       {
1906 	tree arg = TYPE_ARG_TYPES (*tp);
1907 
1908 	/* We never want to walk into default arguments.  */
1909 	for (; arg; arg = TREE_CHAIN (arg))
1910 	  WALK_SUBTREE (TREE_VALUE (arg));
1911       }
1912       break;
1913 
1914     case ARRAY_TYPE:
1915       WALK_SUBTREE (TREE_TYPE (*tp));
1916       WALK_SUBTREE_TAIL (TYPE_DOMAIN (*tp));
1917 
1918     case INTEGER_TYPE:
1919       WALK_SUBTREE (TYPE_MIN_VALUE (*tp));
1920       WALK_SUBTREE_TAIL (TYPE_MAX_VALUE (*tp));
1921 
1922     case OFFSET_TYPE:
1923       WALK_SUBTREE (TREE_TYPE (*tp));
1924       WALK_SUBTREE_TAIL (TYPE_OFFSET_BASETYPE (*tp));
1925 
1926 #ifdef INLINER_FOR_JAVA
1927     case EXIT_BLOCK_EXPR:
1928       WALK_SUBTREE_TAIL (TREE_OPERAND (*tp, 1));
1929 
1930     case SAVE_EXPR:
1931       WALK_SUBTREE_TAIL (TREE_OPERAND (*tp, 0));
1932 #endif /* INLINER_FOR_JAVA */
1933 
1934     default:
1935       abort ();
1936     }
1937 
1938   /* We didn't find what we were looking for.  */
1939   return NULL_TREE;
1940 
1941 #undef WALK_SUBTREE
1942 #undef WALK_SUBTREE_TAIL
1943 }
1944 
1945 /* Like walk_tree, but does not walk duplicate nodes more than
1946    once.  */
1947 
1948 tree
walk_tree_without_duplicates(tree * tp,walk_tree_fn func,void * data)1949 walk_tree_without_duplicates (tree *tp, walk_tree_fn func, void *data)
1950 {
1951   tree result;
1952   htab_t htab;
1953 
1954   htab = htab_create (37, htab_hash_pointer, htab_eq_pointer, NULL);
1955   result = walk_tree (tp, func, data, htab);
1956   htab_delete (htab);
1957   return result;
1958 }
1959 
1960 /* Passed to walk_tree.  Copies the node pointed to, if appropriate.  */
1961 
1962 tree
copy_tree_r(tree * tp,int * walk_subtrees,void * data ATTRIBUTE_UNUSED)1963 copy_tree_r (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1964 {
1965   enum tree_code code = TREE_CODE (*tp);
1966 
1967   /* We make copies of most nodes.  */
1968   if (IS_EXPR_CODE_CLASS (TREE_CODE_CLASS (code))
1969       || TREE_CODE_CLASS (code) == 'c'
1970       || code == TREE_LIST
1971       || code == TREE_VEC
1972       || (*lang_hooks.tree_inlining.tree_chain_matters_p) (*tp))
1973     {
1974       /* Because the chain gets clobbered when we make a copy, we save it
1975 	 here.  */
1976       tree chain = TREE_CHAIN (*tp);
1977 
1978       /* Copy the node.  */
1979       *tp = copy_node (*tp);
1980 
1981       /* Now, restore the chain, if appropriate.  That will cause
1982 	 walk_tree to walk into the chain as well.  */
1983       if (code == PARM_DECL || code == TREE_LIST
1984 #ifndef INLINER_FOR_JAVA
1985 	  || (*lang_hooks.tree_inlining.tree_chain_matters_p) (*tp)
1986 	  || STATEMENT_CODE_P (code))
1987 	TREE_CHAIN (*tp) = chain;
1988 
1989       /* For now, we don't update BLOCKs when we make copies.  So, we
1990 	 have to nullify all scope-statements.  */
1991       if (TREE_CODE (*tp) == SCOPE_STMT)
1992 	SCOPE_STMT_BLOCK (*tp) = NULL_TREE;
1993 #else /* INLINER_FOR_JAVA */
1994 	  || (*lang_hooks.tree_inlining.tree_chain_matters_p) (*tp))
1995 	TREE_CHAIN (*tp) = chain;
1996 #endif /* INLINER_FOR_JAVA */
1997     }
1998   else if (TREE_CODE_CLASS (code) == 't')
1999     *walk_subtrees = 0;
2000 
2001   return NULL_TREE;
2002 }
2003 
2004 /* The SAVE_EXPR pointed to by TP is being copied.  If ST contains
2005    information indicating to what new SAVE_EXPR this one should be
2006    mapped, use that one.  Otherwise, create a new node and enter it in
2007    ST.  FN is the function into which the copy will be placed.  */
2008 
2009 void
remap_save_expr(tree * tp,void * st_,tree fn,int * walk_subtrees)2010 remap_save_expr (tree *tp, void *st_, tree fn, int *walk_subtrees)
2011 {
2012   splay_tree st = (splay_tree) st_;
2013   splay_tree_node n;
2014 
2015   /* See if we already encountered this SAVE_EXPR.  */
2016   n = splay_tree_lookup (st, (splay_tree_key) *tp);
2017 
2018   /* If we didn't already remap this SAVE_EXPR, do so now.  */
2019   if (!n)
2020     {
2021       tree t = copy_node (*tp);
2022 
2023       /* The SAVE_EXPR is now part of the function into which we
2024 	 are inlining this body.  */
2025       SAVE_EXPR_CONTEXT (t) = fn;
2026       /* And we haven't evaluated it yet.  */
2027       SAVE_EXPR_RTL (t) = NULL_RTX;
2028       /* Remember this SAVE_EXPR.  */
2029       n = splay_tree_insert (st,
2030 			     (splay_tree_key) *tp,
2031 			     (splay_tree_value) t);
2032       /* Make sure we don't remap an already-remapped SAVE_EXPR.  */
2033       splay_tree_insert (st, (splay_tree_key) t, (splay_tree_value) t);
2034     }
2035   else
2036     /* We've already walked into this SAVE_EXPR, so we needn't do it
2037        again.  */
2038     *walk_subtrees = 0;
2039 
2040   /* Replace this SAVE_EXPR with the copy.  */
2041   *tp = (tree) n->value;
2042 }
2043 
2044 #ifdef INLINER_FOR_JAVA
2045 /* Add STMT to EXISTING if possible, otherwise create a new
2046    COMPOUND_EXPR and add STMT to it.  */
2047 
2048 static tree
add_stmt_to_compound(tree existing,tree type,tree stmt)2049 add_stmt_to_compound (tree existing, tree type, tree stmt)
2050 {
2051   if (!stmt)
2052     return existing;
2053   else if (existing)
2054     return build (COMPOUND_EXPR, type, existing, stmt);
2055   else
2056     return stmt;
2057 }
2058 
2059 #endif /* INLINER_FOR_JAVA */
2060